package com.asl.mp.util;

import javax.imageio.ImageIO;
import javax.swing.*;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;


public class ImageUtil {

    public static String getBase64ByImgUrl(String url) {
        String suffix = url.substring( url.lastIndexOf( "." ) + 1 );
        try {
            URL urls = new URL( url );
            ByteArrayOutputStream baas = new ByteArrayOutputStream();
            Image image = Toolkit.getDefaultToolkit().getImage( urls );
            BufferedImage biOut = toBufferedImage( image );
            ImageIO.write( biOut, suffix, baas );
            return Base64Util.encode( baas.toByteArray() );
        } catch (Exception e) {
            return "";
        }

    }

    public static BufferedImage toBufferedImage(Image image) {
        if (image instanceof BufferedImage) {
            return (BufferedImage) image;
        }
        // This code ensures that all the pixels in the image are loaded  
        image = new ImageIcon( image ).getImage();
        BufferedImage bimage = null;
        GraphicsEnvironment ge = GraphicsEnvironment
                .getLocalGraphicsEnvironment();
        try {
            int transparency = Transparency.OPAQUE;
            GraphicsDevice gs = ge.getDefaultScreenDevice();
            GraphicsConfiguration gc = gs.getDefaultConfiguration();
            bimage = gc.createCompatibleImage( image.getWidth( null ),
                    image.getHeight( null ), transparency );
        } catch (HeadlessException e) {
            // The system does not have a screen  
        }
        if (bimage == null) {
            // Create a buffered image using the default color model  
            int type = BufferedImage.TYPE_INT_RGB;
            bimage = new BufferedImage( image.getWidth( null ),
                    image.getHeight( null ), type );
        }
        // Copy image to buffered image  
        Graphics g = bimage.createGraphics();
        // Paint the image onto the buffered image  
        g.drawImage( image, 0, 0, null );
        g.dispose();
        return bimage;
    }

    /**
     * 通过图片的url获取图片的base64字符串
     *
     * @param imgUrl 图片url
     * @return 返回图片base64的字符串
     */
    public static String image2Base64(String imgUrl) {

        URL url;
        InputStream is = null;
        ByteArrayOutputStream outStream = null;
        HttpURLConnection httpUrl = null;
        try {
            url = new URL( imgUrl );
            httpUrl = (HttpURLConnection) url.openConnection();
            httpUrl.connect();
            httpUrl.getInputStream();
            is = httpUrl.getInputStream();
            outStream = new ByteArrayOutputStream();
            //创建一个Buffer字符串
            byte[] buffer = new byte[1024];
            //每次读取的字符串长度，如果为-1，代表全部读取完毕
            int len = 0;
            //使用一个输入流从buffer里把数据读取出来
            while ((len = is.read( buffer )) != -1) {
                //用输出流往buffer里写入数据，中间参数代表从哪个位置开始读，len代表读取的长度
                outStream.write( buffer, 0, len );
            }
            // 对字节数组Base64编码
            return Base64Util.encode( outStream.toByteArray() );
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (is != null) {
                try {
                    is.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (outStream != null) {
                try {
                    outStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (httpUrl != null) {
                httpUrl.disconnect();
            }
        }
        return imgUrl;
    }
}